This code turns an Arduino into a motor controller! It provides a simple serial interface to communicate with a high-level computer (e.g. running ROS), and generates the appropriate PWM signals for a motor driver, to drive two motors.
This is a fork of the original code, with some changes, and removal of the ROS nodes (see this repo for an alternative). Check out README-orig.md for the original README.
As I only have need for a subset of the functionality, I have no idea what does and doesn't work, beyond what is detailed below. Feedback/improvements are welcome (though no promises on how quickly I'll respond). I currently only use the L298N driver, and the Arduino encoder mode.
TODO
- Finish this README
The main functionality provided is to receive motor speed requests over a serial connection, and provide encoder feedback. The original code has provisions for other features - e.g. read/write of digital/analog pins, servo control, but I've never used them.
The main commands to know are
e- Motor responds with current encoder counts for each motorr- Reset encoder valueso <PWM1> <PWM2>- Set the raw PWM speed of each motor (-255 to 255)m <Spd1> <Spd2>- Set the closed-loop speed of each motor in counts per loop (Default loop rate is 30, so(counts per sec)/30p <Kp> <Kd> <Ki> <Ko>- Update the PID parameters
Some quick things to note
- There is an auto timeout (default 2s) so you need to keep sending commands for it to keep moving
- PID parameter order is PDI (?)
- Motor speed is in counts per loop
- Default baud rate 57600
- Needs carriage return (CR)
- Make sure serial is enabled (user in dialout group)
- Check out the original readme for more
- Document PID tuning
- Make the speed input counts per second
- Add/test more driver boards
- Add/test other functionality